It's blizzards mistake in creating the joke called D3 but it's not blizzard fault for the economy.
There are currently some players, very hardcore D3 gamers, manipulating the economy.
I know a small group that still has trillions of gold and in game items. From what they tell me, they plan to work the system and make as much real cash as they can from the hack that just happened.
If their doing it, you can be others are as well. Blizzard claims they took out 85% of the duped gold. I'm not sure I believe it.
So far, they have not been caught or rolled back. It could happen in the future but so far the real money their making is substantial and all from duped gold and what they bought with that gold. It's a subtle manipulation of the AH to make prices higher so they get more money.
Personally I doubt blizzard cares cause they still want their cut of the money. How better to make more cash than to let inflation happen even if it's not a natural inflation. They still get their cut. It's a big win for blizzard but in the short term not long I think.